We make long leg boxer shorts in 6 and 9 inch lengths, so we have an interest here.
Updated August 2026. This is general information, not medical advice.
Chub rub is the friction rash you get when your inner thighs rub together. It shows up as redness, stinging, a burning feeling, and in worse cases raw or broken skin. It is extremely common, it has nothing to do with your size, and almost nobody talks about it.
This covers what causes it, what actually stops it, what to do if you are already sore, and how long it takes to heal.
What chub rub is, and what it looks like
Chafing is skin damage caused by repeated friction. When it happens on the inner thighs it gets called chub rub, though the name is misleading: anyone whose thighs touch can get it, at any size, and plenty of very slim people do.
What it looks like on the skin:
- Redness across an area rather than in one spot
- A stinging or burning feeling, often worse than it looks
- Skin that feels hot or slightly swollen
- In worse cases, a raw patch, small blisters, or broken skin that weeps
It usually appears symmetrically, on both inner thighs in roughly the same place. That is one way to tell chafing from a rash with another cause: chafing follows the friction, not a pattern.
What causes it
Two things, and only one of them is about what you wear.
Friction. Skin moving against skin. Every step is thousands of small rubs, and eventually the top layer of skin gives up.
Moisture. This is the part most people get wrong. A little sweat is worse than none, because damp skin is tacky rather than slippery, so it grips instead of gliding. It is why chafing is worse on humid days than dry hot ones, and why it starts sooner on a long walk than a short one.
When it tends to happen: hot and humid weather, long days on your feet, exercise, wearing dresses or skirts with nothing between your thighs, weight change in either direction, pregnancy and the months after, and perimenopause when sweating becomes less predictable.
What most people try first, and why it stops working
If you are reading this you have probably already tried two or three of these.
| What you tried | Why it did not last |
|---|---|
| Anti-chafe balm or stick | Sweats off in two or three hours. Fine for a run, not for a day out, and you have to remember to reapply |
| Talc or powder | Works until you sweat, then clumps. Can irritate on already-sore skin |
| Barrier cream or petroleum jelly | Cheap and genuinely effective for a few hours. Same problem: it wears off, and it can mark clothing |
| Cycling shorts | The coverage is right but they are too warm under a dress, and the seams still sit on the inner thigh |
| Plasters or kinesiology tape | Comes loose once you are warm, and taking it off hurts more than the chafing did |
| Thigh bands | Better than nothing, but they roll and they only cover a narrow strip |
| Longer cotton knickers | Roll up within the hour. The roll becomes a rope at the top of your thigh, and now that is the thing rubbing |
| Just putting up with it | The most common one, and the reason the category barely existed until recently |
The pattern: most of these treat the skin. Very few put something durable between your thighs and keep it there.
What actually stops it
Coverage is the thing that works. A smooth layer between your thighs means they slide past each other instead of catching. It is the only approach that does not wear off, sweat off, or need reapplying.
The specification that matters is leg length. Most underwear marketed to women stops between 2 and 4 inches down the thigh, which is short of where thighs actually touch. You need 6 inches or more.
The second thing that matters is the leg band. A band that rolls into a rope at the top of your thigh is worse than no coverage at all, because the rope becomes the thing rubbing. This is why so many people try longer cotton knickers, find they roll, and give up on the whole approach.
The third is fabric. Anything that holds damp against the skin makes chafing worse, so you want something breathable that moves moisture rather than absorbing and keeping it. We go through the options in our guide to moisture wicking underwear.
We make anti-chafing shorts in 6 and 9 inch lengths, so we have an interest here. But the mechanism is the same whoever you buy from: check the inseam measurement, not the product name.
These are very comfortable and cool to wear. Prevents chafing when wearing dresses. They have been a godsend in this hot weather. They wash well too!
Marlene, UK, verified review
If you are already sore
Prevention is one thing. Skin that has already gone is another, and almost nobody covers it.
- Cool the area. Cool water or a cool compress, not ice directly on skin
- Dry it properly. Pat rather than rub, and let the air get to it before you dress
- Use a barrier. A simple zinc oxide or petroleum-based barrier protects the skin while it heals. Skip anything perfumed, and skip anything with alcohol in it
- Wear something loose overnight. Skin heals faster with air on it
- Give it a day if you can. Chafed skin that keeps being chafed does not heal
Do not exfoliate it, do not put antiseptic on broken skin unless a pharmacist tells you to, and do not go straight back into the thing that caused it.
How long does chafing take to heal?
Mild chafing, where the skin is red and sore but unbroken, usually settles in one to three days if you keep the area clean, dry and free from further rubbing.
Broken or weeping skin takes longer, typically five to ten days, and healing is much slower if you keep chafing the same spot. That is the main reason chafing seems to last for weeks: it is not one injury healing slowly, it is the same skin being re-damaged daily.
See a pharmacist or your GP if: the skin is broken and weeping, it is not improving after a few days, the redness is spreading, the area feels hot or swollen, or there is pus. Chafed skin can become infected and it is worth catching early.
Chafing in other places
The same friction-and-moisture rule applies wherever skin meets skin or fabric.
Groin. Common in hot weather and after exercise. The same advice applies: keep it dry, use a barrier, wear something breathable. If it is persistent, itchy and not improving, see a pharmacist, because fungal infections in that area look similar and need different treatment.
Under the bust. A soft cotton or bamboo layer helps, as does making sure the area is fully dry after showering.
At the gym. Squats, classes and anything on a mat make it worse, and normal underwear rides up exactly when you need it not to. We cover what to wear in our gym underwear guide.
Running and cycling. Different problem, because it is repeated motion over a long period. Technical fabrics with flat seams work better here than natural fibres, since managing sweat matters more than softness. We compare the options in our running comparison.
Long walks and hiking. The most common trigger after hot weather. We compare merino, synthetic and bamboo options in our hiking underwear guide.
Nipples. Mostly a running problem, and tape or a barrier balm is the usual answer.
Questions
What is chub rub?
The everyday name for chafing on the inner thighs. It is skin damage caused by friction, made worse by sweat, and it happens to people of every size.
How do I stop chub rub?
The only approach that lasts all day is putting something smooth between your thighs, with a leg long enough to reach where they actually touch, usually 6 inches or more. Balms, powders and barrier creams work for a few hours and then wear off.
Does chub rub mean I am overweight?
No. The name is unhelpful and a lot of people dislike it for that reason. It happens to anyone whose thighs touch when they walk, which includes plenty of very slim people, and it happens more in hot weather regardless of size.
How long does chub rub take to heal?
One to three days for mild redness, five to ten days if the skin has broken, and much longer if you keep chafing the same area before it has healed.
What cream is best for chub rub?
For prevention, a simple barrier balm or petroleum jelly works for a few hours. For skin that is already sore, a zinc oxide barrier cream is the usual choice. Ask a pharmacist rather than guessing, particularly if the skin is broken.
Can chafing get infected?
Yes, if the skin breaks. Signs to watch for are spreading redness, heat, swelling or pus. See a pharmacist or GP if any of those appear.
Do anti-chafing shorts work?
For skin-on-skin thigh rub, yes, and the mechanism is simple: they put a smooth layer between your thighs. What decides whether a pair works is the leg length. We go through what to look for on our anti-chafing shorts page.
Is chub rub worse in summer?
Yes, for two reasons. More sweat, which makes skin tacky rather than slippery, and fewer layers, so there is often nothing between your thighs at all.
